Can Laser Rangefinder Module be Used for Obstacle Avoidance as Other Sensors?

Obstacle avoidance is the bedrock of autonomous navigation for robots, drones, AGVs, and countless other smart machines. When choosing sensors for this critical task, engineers often turn to ultrasonics, infrared (IR), cameras, or sophisticated LiDAR systems. But what about the humble laser rangefinder module – those compact, relatively inexpensive components found in everything from tape measures to industrial equipment? Can they step up as a viable solution for obstacle avoidance? The answer is a nuanced "Yes, but with significant caveats and specific use cases."

Understanding the Contenders

Before diving into laser rangefinders, let's quickly recap common obstacle avoidance sensors:

Ultrasonic Sensors: 

Emit sound waves and measure echo time. Pros: Inexpensive, unaffected by lighting/color, good for short-medium range. Cons: Wide beam angle (poor directionality), susceptible to acoustic noise, slow update rates, poor performance on soft/absorbent surfaces.

Infrared (IR) Proximity Sensors: 

Measure reflected IR light intensity. Pros: Very cheap, simple. Cons: Short range, highly sensitive to surface color/reflectivity and ambient IR light (sunlight), provide proximity rather than precise distance, unreliable outdoors.

Monocular/Stereo Cameras: 

Capture visual data. Pros: Rich contextual information (shape, texture), long range potential. Cons: Computationally intensive (requires complex algorithms like SLAM, CNN-based detection), performance degrades heavily in low light, fog, or glare, calibration sensitive.

LiDAR (Light Detection and Ranging): 

Emits rapid laser pulses across a wide field of view (FOV), creating a detailed 2D or 3D point cloud of the environment. Pros: High accuracy, high resolution, long range, works well in varying light. Cons: Expensive, complex, power-hungry, can be affected by certain atmospheric conditions and highly reflective surfaces.

Where Laser Rangefinder Modules Fit In

Laser rangefinder modules typically operate on the Time-of-Flight (ToF) principle. They emit a focused laser beam (usually infrared 905nm and 1535nm, Class 1 eye-safe) and precisely measure the time it takes for the light to reflect off a target and return. This provides highly accurate distance measurements to a single point.

Comparison with Other Sensors

Advantages for Obstacle Avoidance

High Accuracy & Long Range:

Unlike ultrasonic and IR sensors (limited to a few meters), long-range laser modules can detect obstacles at tens or even hundreds of meters with meter-level accuracy.

Narrow Beam Angle for Precision:

Ultrasonic sensors suffer from wide beam dispersion (30°–60°), making them poor for precise detection. While laser rangefinders have beam divergence as small as 0.1mrad–3mrad, allowing precise targeting of distant obstacles .

Limitations for Obstacle Avoidance

Despite their strengths, long-range laser rangefinders have key limitations:

Single-Point Detection (No Wide Field of View):

Unlike LiDAR (which scans 360°), a single laser module only detects obstacles directly in its beam path.

Limited Performance on Certain Surfaces:

Highly reflective surfaces (mirrors, glass) can cause false readings. While dark or absorbent materials (black foam, fabric) may reduce maximum range.

No Object Classification:

They provide distance only, not object shape or type (unlike cameras or 3D LiDAR).

Conclusion

Laser rangefinder modules can act as capable obstacle-avoidance sensors—especially when fused with other sensors or algorithms. For UAVs, mobile robots, and AGV systems, LRFs offer a compelling balance of precision, cost, and performance. However, optimal results come when integrating them into multi-sensor frameworks and intelligent planning algorithms.

References

1. Benewake. (2023). *TF03 Long-Distance LiDAR Sensor Datasheet*.

2. STMicroelectronics. (2022). *VL53L5CX: Multi-Zone ToF Sensor*.

3. Niclass, C., et al. (2014). *A 0.18μm CMOS SoC for a 100m-Range ToF Depth Sensor*. IEEE JSSC.

4. Zhou, B., et al. (2020). Autonomous UAV Navigation Using Multi-Sensor Fusion. IEEE T-RO.

The author

About the Author & Team, Eyoung Tech

Hey, this is EyoungTech, a China-based professional team dedicated to advancing optoelectronic innovation.

With a steadfast focus on optoelectronic products represented by laser rangefinders and UAV payload pods, we deliver comprehensive, end-to-end solutions to leading international partners in the UAV & drone and defence sector. Backed by years of collective expertise, our stable, highly skilled workforce ensures rock-solid technical performance and unwavering support at every stage — from initial design through deployment and beyond. At Eyoung Technology, your mission success is our top priority.

The purpose of this article is to share with insight related to cutting-edge technlogy and product applications in defence, surveying of drone industry.

5km Laser Range Finder Module for UAV Optical System

6-8km High Precision Laser Range Finder Module

Small Gimbal Camera with Three-sensor

The Role of Range Resolution in Laser Range Finders

Laser Ranging device: A Good Helper for Measuring Distance

The Advantages of a Lightweight Laser Rangefinder Module